Antibody-based therapies have a proven record of efficacy against many diseases including inflammatory disorders, cancers, infectious diseases, and solid organ transplant rejection. Currently, more than 40 therapeutic monoclonal antibodies (mAbs) are approved for clinical use in USA, EU and several other countries. Most of those are for therapy of cancer and immune diseases. Examples of therapeutic antibodies with anti-tumor activities include anti-CD20, anti-Her2, anti-EGFR, anti-CD40, anti-CTLA-4, and anti-PD-1 antibodies.
The majority of approved biopharmaceuticals are produced in mammalian cell culture systems to deliver proteins with desired glycosylation patterns and thus ensure reduced immunogenicity and higher in vivo efficacy and stability. Non-human mammalian expression systems such as CHO or NS0 cells have the machinery required to add complex, human-type glycans. However, glycans produced in these systems can differ from glycans produced in humans. Their glycosylation machinery often adds undesired carbohydrate determinants which may alter protein folding, induce immunogenicity, and reduce circulatory life span of the drug.
Furthermore, mammalian cell culture delivers a heterogeneous mixture of glycosylation patterns which do not all have the same properties. Properties like safety, efficacy and the serum half-life of therapeutic proteins can be affected by these glycosylation patterns. The mammalian cell culture system delivers heterogeneous mixtures of glycosylation patterns which do not all have the same properties.